I've recently created a dev board for an ATXMEGA32a4u. After building the PCB, I cannot get the device to enumerate (I believe that's the right term) or show up as connected to a USB port in USBView.
Here is a link to my schematic/board layout screenshots: https://imgur.com/a/oh0Ap
Note the LDO is an NCP1117.
I've tried a few different things that I've seen on other XMEGA dev boards I've found on here, but nothing has improved my situation:
- Removing the 22 ohm resistors on the USB lines
- I added a pull-up line to the reset switch w/ a 10k resistor and without
- I tried entering bootloader mode by shorting PC3 to ground as per AVR1916
I read on one topic on here (cannot find link, sorry) that the 32a4u does not ship with a bootloader, and I'll need to flash one myself to get it to recognize via USB? Which tool will I need to do that?